US4047886A - Furnace for the continuous sintering of pellets of ceramic nuclear fuel material - Google Patents

Furnace for the continuous sintering of pellets of ceramic nuclear fuel material Download PDF

Info

Publication number
US4047886A
US4047886A US05/634,629 US63462975A US4047886A US 4047886 A US4047886 A US 4047886A US 63462975 A US63462975 A US 63462975A US 4047886 A US4047886 A US 4047886A
Authority
US
United States
Prior art keywords
containers
furnace
lock
pellets
sintering
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US05/634,629
Inventor
Jacques Heyraud
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Commissariat a lEnergie Atomique et aux Energies Alternatives CEA
Original Assignee
Commissariat a lEnergie Atomique CEA
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Commissariat a lEnergie Atomique CEA filed Critical Commissariat a lEnergie Atomique CEA
Priority to US05/634,629 priority Critical patent/US4047886A/en
Application granted granted Critical
Publication of US4047886A publication Critical patent/US4047886A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
    • B22F3/003—Apparatus, e.g. furnaces
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27B—FURNACES, KILNS, OVENS OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
    • F27B9/00—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity
    • F27B9/04—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity adapted for treating the charge in vacuum or special atmosphere
    • F27B9/045—Furnaces with controlled atmosphere
    • F27B9/047—Furnaces with controlled atmosphere the atmosphere consisting of protective gases
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27B—FURNACES, KILNS, OVENS OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
    • F27B9/00—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity
    • F27B9/30—Details, accessories or equipment specially adapted for furnaces of these types
    • F27B9/38—Arrangements of devices for charging
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D3/00—Charging; Discharging; Manipulation of charge
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D5/00—Supports, screens or the like for the charge within the furnace
    • F27D5/0068—Containers
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27B—FURNACES, KILNS, OVENS OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
    • F27B9/00—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity
    • F27B9/12—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity with special arrangements for preheating or cooling the charge
    • F27B2009/122—Preheating
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27B—FURNACES, KILNS, OVENS OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
    • F27B9/00—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity
    • F27B9/06—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity heated without contact between combustion gases and charge; electrically heated
    • F27B9/062—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity heated without contact between combustion gases and charge; electrically heated electrically heated
    • F27B9/063—Resistor heating, e.g. with resistors also emitting IR rays
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D3/00—Charging; Discharging; Manipulation of charge
    • F27D2003/0034—Means for moving, conveying, transporting the charge in the furnace or in the charging facilities
    • F27D2003/0059—Means for moving, conveying, transporting the charge in the furnace or in the charging facilities comprising tracks, e.g. rails and wagon
    • F27D2003/006—Means for moving, conveying, transporting the charge in the furnace or in the charging facilities comprising tracks, e.g. rails and wagon with a return track
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D9/00—Cooling of furnaces or of charges therein
    • F27D2009/0002—Cooling of furnaces
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D19/00—Arrangements of controlling devices
    • F27D2019/0028—Regulation
    • F27D2019/0071—Regulation using position sensors
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D21/00—Arrangement of monitoring devices; Arrangement of safety devices
    • F27D2021/0057—Security or safety devices, e.g. for protection against heat, noise, pollution or too much duress; Ergonomic aspects
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D99/00—Subject matter not provided for in other groups of this subclass
    • F27D99/0073—Seals
    • F27D2099/0078—Means to minimize the leakage of the furnace atmosphere during charging or discharging
    • F27D2099/008—Using an air-lock
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D3/00—Charging; Discharging; Manipulation of charge
    • F27D3/04—Ram or pusher apparatus
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27M—INDEXING SCHEME RELATING TO ASPECTS OF THE CHARGES OR FURNACES, KILNS, OVENS OR RETORTS
    • F27M2002/00—Disposition of the charge
    • F27M2002/03—Disposition of the charge as a batch of articles in a basket
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27M—INDEXING SCHEME RELATING TO ASPECTS OF THE CHARGES OR FURNACES, KILNS, OVENS OR RETORTS
    • F27M2003/00—Type of treatment of the charge
    • F27M2003/04—Sintering
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27M—INDEXING SCHEME RELATING TO ASPECTS OF THE CHARGES OR FURNACES, KILNS, OVENS OR RETORTS
    • F27M2003/00—Type of treatment of the charge
    • F27M2003/15—Vaporisation
    • F27M2003/155—Condensation

Definitions

  • This invention relates to a continuous furnace for sintering ceramic nuclear fuel materials which are usually produced in the form of pellets.
  • the fabrication of nuclear fuels in the form of pellets involves shaping of a compact consisting of powdered fuel coated with binder followed successively by preheating which causes the removal of binder components and heating in a reducing or neutral controlled atmosphere during which the sintering operation proper takes place.
  • the essential aim of this invention is to provide a furnace in which the material to be sintered is circulated continuously and automatically while being maintained continuously in the controlled atmosphere which has been chosen. Moreover, the removal of the binding agents must take place in a suitable manner within a zone located close to the preheating zone in order to prevent contamination of the material during sintering by the gases which result from decomposition of the binding agents.
  • the invention is concerned with a furnace for the continuous sintering of pellets of ceramic nuclear fuel material in a neutral or reducing atmosphere, of the type comprising a tubular enclosure having a longitudinal axis and equipped with heating means located at intervals along said enclosure, a hearth for the longitudinal displacement of pellet containers, means for injecting gas at both ends of the furnace, means for sucking gas in an intermediate zone between the preheating and sintering zones and for condensing the binder contained therein, and means for displacing said containers along said hearth from a lock-chamber for the introduction of containers which is placed at one end of the furnace to a lock-chamber for the extraction of containers at the other end of the furnace, characterized in that the two lock-chambers are connected to each other in leak-tight manner by means of a conveyor belt which passes through a glove box, there being juxtaposed within said glove box a station for loading containers with sub-containers which contain the pellets to be sintered and a station for unloading said sub-containe
  • the containers move in a closed circuit and all the operations are performed automatically in a controlled atmosphere.
  • the furnace which is shown in this FIGURE essentially comprises a cylindrical furnace A equipped with heating means (not shown) constituted by electric resistors located at intervals along its length.
  • One end of the furnace is connected to a lock-chamber B for the introduction of containers loaded with pellets to be sintered and the other end is connected to a lock-chamber C for the ejection of containers loaded with sintered pellets.
  • the two lock-chambers are connected to each other by means of a conveyor belt D which passes through a glove box E.
  • the furnace A is made of eight cylindrical elements T 1 to T 8 .
  • the element T 1 is a preheating element whilst the element T 2 is an element for the removal of binding agents within a condenser 1.
  • the elements T 3 to T 8 are sintering elements.
  • the furnace also comprises a cylindrical element 2 fitted with a connecting chamber 3 associated with the introduction chamber B.
  • the successive movements of thrust of said jack produce a step-by-step displacement of the continuous train of containers along the hearth of the furnace.
  • the jack V 5 is actuated either by a low-speed forward-motion motor or by a high-speed return motor, the movement of backward return being initiated by an end-of-travel contact.
  • the lock-chamber B is equipped with two doors P 1 and P 2 and with two jacks V 3 and V 4 .
  • On the element T 8 is fixed a frusto-conical element 5 extended by a connecting chamber 6 into which open a pipe 7 for the admission of gas and a jack V 6 .
  • the connecting chamber 6 is associated with the lock-chamber C by means of a door P 3 .
  • the lock-chamber C additionally comprises a jack V 7 and a door P 4 for establishing a communication with a passage 8 in which the conveyor belt D is capable of displacement.
  • the lock-chambers B and C are each fitted with two pipes (not shown) for the injection and discharge of a gas in order to ensure that each lock-chamber can contain at any moment an atmosphere corresponding to that of the upstream or downstream enclosure with which it is intended to be put into communication.
  • pellets to be sintered which are formed for example of mixed uranium and plutonium oxide are poured into small metallic vessels or sub-containers 9 of molybdenum, for example, which contain approximately 1.5 Kg of fuel pellets.
  • the sub-containers which have thus been filled are introduced into the glove box E (arrow 10).
  • Two sub-containers are then brought to the loading station 11 by transfer mans (which have not been illustrated in order to avoid complication of the drawing).
  • a jack V 1 serves to transfer said sub-containers into a container 14 which has been brought to an oppositely-facing location by the conveyor belt D.
  • the loading station 13 is placed within the groove box E next to the loading station 11 and comprises a jack V 8 for the ejection of sub-containers which contain the sintered pellets; these latter are placed in a storage position prior to discharge from the glove box (arrow 12).
  • Detectors D 1 and D 2 ensure coordination of the displacement of the conveyor belt and of the jacks V 8 and V 1 as will be explained hereinafter.
  • Two sub-containers 9 are thrust forward by the jack V 1 at the loading station 11 into a sintering container 14. During this stage, the conveyor belt D is stationary and the container is placed in a preset position for the purpose of loading.
  • the conveyor belt is started-up again and stopped automatically by means of an end-of-travel contact when the container has reached the entrance of the lock-chamber B.
  • the doors P 1 and P 2 of the lock-chamber B are closed while this latter is being swept by a gas which is identical with the gas contained in the enclosure E and which can consist of nitrogen, for example.
  • a gas which is identical with the gas contained in the enclosure E and which can consist of nitrogen, for example.
  • the door P 1 is opened, the jacks V 2 and V 3 push the container into the interior of the lock-chamber B.
  • the door P 1 is again closed.
  • the nitrogen contained in the lock-chamber B is removed and this latter is then filled with the gas employed for the sintering operation, for example hydrogen.
  • the door P 2 is opened.
  • the jack V 4 pushes the container into the connecting chamber 3, the jack V 5 being then located in its rear position.
  • the door P 2 is closed again.
  • the jack V 5 pushes the container towards the furnace
  • an end-of-travel contact (not shown) stops the thrust of the jack V 5 which is returned to the rear position.
  • the jack V 6 directs the container towards the lock-chamber C, the door P 3 being then opened and the lock-chamber C filled with hydrogen.
  • the lock-chamber C is swept with nitrogen.
  • the door P 4 is opened.
  • the jack V 7 pushes the container onto the conveyor belt D which is set in motion.
  • the door P 4 is again closed, the lock-chamber C is swept with hydrogen and the door P 3 is again opened.
  • the container is transported to the unloading station 13, the detector D 1 initiates the stopping of the conveyor belt and the forward displacement of the jack 8 which ejects the sub-containers 9.
  • the jack 8 then returns to the rest position and the conveyor belt is again set in motion. If the detector D 2 detects the presence of sub-containers 9, said detector stops the conveyor belt at the loading station 11.
  • the jack V 1 guides the sub-containers 9 into the containers 14 and then returns to its inactive position while the conveyor belt transfers the container 14 to the furnace.
  • the container is stopped at the loading station only if the presence of sub-containers has been detected.
  • the detection systems constituted by the detectors are of particular interest at the moment of starting and at the moment of stopping of a sintering cycle.
  • the pellet containers travel in a closed circuit and are continuously maintained in the controlled atmosphere which has been chosen. Displacement of the containers takes place automatically; these latter form within the furnace A a continuous train which is transferred in step-by-step motion under the thrust of the jack V 5 whilst the conveyor belt D contains at any given moment a maximum of one container during transfer between the lock-chambers C and B.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Tunnel Furnaces (AREA)

Abstract

The furnace comprises a hearth for the longitudinal displacement of pellet containers, means for injecting gas at both ends of the furnace, for sucking gas between preheating and sintering zones and for condensing the binder, means for displacing the containers from an introduction lock-chamber to an extraction lock-chamber, a conveyor belt which passes through a glove box and provides a leak-tight connection between the lock-chambers. A station for loading containers with pellet sub-containers prior to sintering and a station for unloading the pellet sub-containers after sintering are juxtaposed within the glove box.

Description

This invention relates to a continuous furnace for sintering ceramic nuclear fuel materials which are usually produced in the form of pellets.
The fabrication of nuclear fuels in the form of pellets involves shaping of a compact consisting of powdered fuel coated with binder followed successively by preheating which causes the removal of binder components and heating in a reducing or neutral controlled atmosphere during which the sintering operation proper takes place.
The essential aim of this invention is to provide a furnace in which the material to be sintered is circulated continuously and automatically while being maintained continuously in the controlled atmosphere which has been chosen. Moreover, the removal of the binding agents must take place in a suitable manner within a zone located close to the preheating zone in order to prevent contamination of the material during sintering by the gases which result from decomposition of the binding agents.
The invention is concerned with a furnace for the continuous sintering of pellets of ceramic nuclear fuel material in a neutral or reducing atmosphere, of the type comprising a tubular enclosure having a longitudinal axis and equipped with heating means located at intervals along said enclosure, a hearth for the longitudinal displacement of pellet containers, means for injecting gas at both ends of the furnace, means for sucking gas in an intermediate zone between the preheating and sintering zones and for condensing the binder contained therein, and means for displacing said containers along said hearth from a lock-chamber for the introduction of containers which is placed at one end of the furnace to a lock-chamber for the extraction of containers at the other end of the furnace, characterized in that the two lock-chambers are connected to each other in leak-tight manner by means of a conveyor belt which passes through a glove box, there being juxtaposed within said glove box a station for loading containers with sub-containers which contain the pellets to be sintered and a station for unloading said sub-containers which contain the sintered pellets.
By means of this arrangement, the containers move in a closed circuit and all the operations are performed automatically in a controlled atmosphere.
Further characteristic features and advantages of the invention will in any case become apparent from the description which is given hereinafter and relates to one example of a sintering furnace which is given without any implied limitation, reference being made to the accompanying drawings in which the single FIGURE is a view partly in section of a preferred embodiment of the present furnace.
The furnace which is shown in this FIGURE essentially comprises a cylindrical furnace A equipped with heating means (not shown) constituted by electric resistors located at intervals along its length. One end of the furnace is connected to a lock-chamber B for the introduction of containers loaded with pellets to be sintered and the other end is connected to a lock-chamber C for the ejection of containers loaded with sintered pellets. The two lock-chambers are connected to each other by means of a conveyor belt D which passes through a glove box E.
The furnace A is made of eight cylindrical elements T1 to T8. The element T1 is a preheating element whilst the element T2 is an element for the removal of binding agents within a condenser 1. The elements T3 to T8 are sintering elements.
Separate cooling coils (not shown in the FIGURE) are fixed by brazing around the condenser 1 and the furnace elements. This accordingly minimizes the danger of flooding within the furnace which might occur with a jacket-type cooling system and the attendant danger of explosion arising from the rapid vaporization which would consequently take place. The danger of reaching the critical state due to a possible contact between water and fissile material is also minimized.
The furnace also comprises a cylindrical element 2 fitted with a connecting chamber 3 associated with the introduction chamber B.
A pipe 4 for the injection of gas and a jack V5 open into the connecting chamber 3. The successive movements of thrust of said jack produce a step-by-step displacement of the continuous train of containers along the hearth of the furnace.
The jack V5 is actuated either by a low-speed forward-motion motor or by a high-speed return motor, the movement of backward return being initiated by an end-of-travel contact.
The lock-chamber B is equipped with two doors P1 and P2 and with two jacks V3 and V4. On the element T8 is fixed a frusto-conical element 5 extended by a connecting chamber 6 into which open a pipe 7 for the admission of gas and a jack V6. The connecting chamber 6 is associated with the lock-chamber C by means of a door P3. The lock-chamber C additionally comprises a jack V7 and a door P4 for establishing a communication with a passage 8 in which the conveyor belt D is capable of displacement.
The lock-chambers B and C are each fitted with two pipes (not shown) for the injection and discharge of a gas in order to ensure that each lock-chamber can contain at any moment an atmosphere corresponding to that of the upstream or downstream enclosure with which it is intended to be put into communication.
The pellets to be sintered which are formed for example of mixed uranium and plutonium oxide are poured into small metallic vessels or sub-containers 9 of molybdenum, for example, which contain approximately 1.5 Kg of fuel pellets.
The sub-containers which have thus been filled are introduced into the glove box E (arrow 10). Two sub-containers are then brought to the loading station 11 by transfer mans (which have not been illustrated in order to avoid complication of the drawing). At the loading station, a jack V1 serves to transfer said sub-containers into a container 14 which has been brought to an oppositely-facing location by the conveyor belt D.
The loading station 13 is placed within the groove box E next to the loading station 11 and comprises a jack V8 for the ejection of sub-containers which contain the sintered pellets; these latter are placed in a storage position prior to discharge from the glove box (arrow 12). Detectors D1 and D2 ensure coordination of the displacement of the conveyor belt and of the jacks V8 and V1 as will be explained hereinafter.
The operation of the furnace can be deduced from the foregoing and will therefore be described below only in brief outline.
Two sub-containers 9 are thrust forward by the jack V1 at the loading station 11 into a sintering container 14. During this stage, the conveyor belt D is stationary and the container is placed in a preset position for the purpose of loading.
The conveyor belt is started-up again and stopped automatically by means of an end-of-travel contact when the container has reached the entrance of the lock-chamber B. The doors P1 and P2 of the lock-chamber B are closed while this latter is being swept by a gas which is identical with the gas contained in the enclosure E and which can consist of nitrogen, for example. When filling with nitrogen has been completed, the door P1 is opened, the jacks V2 and V3 push the container into the interior of the lock-chamber B. The door P1 is again closed. The nitrogen contained in the lock-chamber B is removed and this latter is then filled with the gas employed for the sintering operation, for example hydrogen. The door P2 is opened. The jack V4 pushes the container into the connecting chamber 3, the jack V5 being then located in its rear position. The door P2 is closed again. The jack V5 pushes the container towards the furnace.
When the container arrives within the connecting chamber 6 at the level of the jack V6, an end-of-travel contact (not shown) stops the thrust of the jack V5 which is returned to the rear position. The jack V6 directs the container towards the lock-chamber C, the door P3 being then opened and the lock-chamber C filled with hydrogen.
After closure of the door P3, the lock-chamber C is swept with nitrogen. On completion of the sweeping operation, the door P4 is opened. The jack V7 pushes the container onto the conveyor belt D which is set in motion. The door P4 is again closed, the lock-chamber C is swept with hydrogen and the door P3 is again opened. At the same time, the container is transported to the unloading station 13, the detector D1 initiates the stopping of the conveyor belt and the forward displacement of the jack 8 which ejects the sub-containers 9. The jack 8 then returns to the rest position and the conveyor belt is again set in motion. If the detector D2 detects the presence of sub-containers 9, said detector stops the conveyor belt at the loading station 11. The jack V1 then guides the sub-containers 9 into the containers 14 and then returns to its inactive position while the conveyor belt transfers the container 14 to the furnace. The container is stopped at the loading station only if the presence of sub-containers has been detected.
The detection systems constituted by the detectors are of particular interest at the moment of starting and at the moment of stopping of a sintering cycle.
It is important to note that, by virtue of the means described in the foregoing, the pellet containers travel in a closed circuit and are continuously maintained in the controlled atmosphere which has been chosen. Displacement of the containers takes place automatically; these latter form within the furnace A a continuous train which is transferred in step-by-step motion under the thrust of the jack V5 whilst the conveyor belt D contains at any given moment a maximum of one container during transfer between the lock-chambers C and B.
It is readily apparent that the invention is not limited to the embodiments which have been more especially described with reference to the FIGURE but is intended on the contrary to cover all alternative forms.

Claims (3)

What we claim is:
1. A furnace for the continuous sintering of pellets of ceramic nuclear fuel material in a neutral or reducing atmosphere, comprising a tubular enclosure having a longitudinal axis and equipped with heating means located at intervals along said enclosure, a hearth for the longitudinal displacement of pellet containers, means for injecting gas at both ends of the furnace, means for sucking gas in an intermediate zone between the preheating and sintering zones and for condensing a binder for the pellets, and means for displacing said containers along said hearth from a lock-chamber for the introduction of containers which is placed at one end of the furnace to a lock-chamber for the extraction of containers at the other end of the furnace, wherein the two lock-chambers are connected to each other in leak-tight manner by means of a conveyor belt which passes through a glove box, there being juxtaposed within said glove box a station for loading containers with sub-containers which contain the pellets to be sintered and a station for unloading said sub-containers which contain the sintered pellets.
2. A sintering furnace according to claim 1, wherein a system for detecting the presence or absence of sub-containers in a container is associated with the unloading station and means for detecting the presence or absence of sub-containers located opposite to the loading station is associated with said loading station.
3. A sintering furnace according to claim 1, wherein the furnace and the binder condenser comprise external cooling means constituted by separate coil-tubes which are brazed onto the frame of the furnace elements or onto the frame of the binder condenser.
US05/634,629 1975-11-24 1975-11-24 Furnace for the continuous sintering of pellets of ceramic nuclear fuel material Expired - Lifetime US4047886A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US05/634,629 US4047886A (en) 1975-11-24 1975-11-24 Furnace for the continuous sintering of pellets of ceramic nuclear fuel material

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US05/634,629 US4047886A (en) 1975-11-24 1975-11-24 Furnace for the continuous sintering of pellets of ceramic nuclear fuel material

Publications (1)

Publication Number Publication Date
US4047886A true US4047886A (en) 1977-09-13

Family

ID=24544586

Family Applications (1)

Application Number Title Priority Date Filing Date
US05/634,629 Expired - Lifetime US4047886A (en) 1975-11-24 1975-11-24 Furnace for the continuous sintering of pellets of ceramic nuclear fuel material

Country Status (1)

Country Link
US (1) US4047886A (en)

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2412803A1 (en) * 1977-12-23 1979-07-20 Alkem Gmbh Continuous furnace for e.g. sintering nuclear fuel pellets - incorporates stop-start mechanism giving exact regulation of heating time
US4214868A (en) * 1978-06-21 1980-07-29 Itoh Iron & Steel Works Co. Ltd. Method of and an apparatus for soaking steel pieces
FR2487491A1 (en) * 1980-07-25 1982-01-29 Bmi Vacuum furnace for continuous heat treatment of metals - esp. for hardening saw blades made of high speed steel
US4396050A (en) * 1980-08-15 1983-08-02 Vandagriff Ralph L Log preparation for veneer peeling
US4518353A (en) * 1983-06-27 1985-05-21 Chugai Ro Co., Ltd. Vacuum sintering furnace
US4527974A (en) * 1981-10-14 1985-07-09 Dario Carraroli Ceramic roller-hearth kiln with controlled combustion and cooling
US4666402A (en) * 1985-05-30 1987-05-19 Flakt Ab Method and apparatus for preheating scrap in a bucket
US4846717A (en) * 1988-03-30 1989-07-11 American Wheels De Mexico, S.A.D. E C.V. Continuous method and apparatus for the thermal treatment of metallic workpieces
EP0230740A3 (en) * 1985-12-11 1989-08-09 Australian Nuclear Science And Technology Organisation Container heating or sintering arrangements and methods
EP0234489A3 (en) * 1986-02-22 1989-08-30 Mahler Dienstleistungs-GmbH Löten-Härten-Anlagenbau Continuous furnace for heating and successively cooling work pieces
US5613847A (en) * 1994-07-01 1997-03-25 Hans Lingl Anlagenbau Und Verfahrenstechnik Gmbh & Co. Heat transfer in a tunnel kiln
US6045357A (en) * 1997-09-22 2000-04-04 Japan Nuclear Cycle Development Institute Continuous sintering plant integrated with glove box for maintenance use
US20100044892A1 (en) * 2006-01-10 2010-02-25 Areva Inc Separating Device For Sintering Shoes
US20180212206A1 (en) * 2016-04-19 2018-07-26 Boe Technology Group Co., Ltd. Sintering apparatus, packaging system for organic light emitting diode device and sintering method
WO2022068053A1 (en) * 2020-09-30 2022-04-07 苏州汇科机电设备有限公司 New atmosphere protection kiln

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3063878A (en) * 1958-05-07 1962-11-13 Wilson Lee Method of and apparatus for annealing
US3778221A (en) * 1969-02-26 1973-12-11 Allegheny Ludlum Ind Inc Annealing furnace and method for its operation
US3884624A (en) * 1973-08-15 1975-05-20 Combustion Eng Nuclear fuel preheating system
US3905758A (en) * 1973-07-13 1975-09-16 Ceraver Heat treatment tunnel kiln for products having a circular cross-section

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3063878A (en) * 1958-05-07 1962-11-13 Wilson Lee Method of and apparatus for annealing
US3778221A (en) * 1969-02-26 1973-12-11 Allegheny Ludlum Ind Inc Annealing furnace and method for its operation
US3905758A (en) * 1973-07-13 1975-09-16 Ceraver Heat treatment tunnel kiln for products having a circular cross-section
US3884624A (en) * 1973-08-15 1975-05-20 Combustion Eng Nuclear fuel preheating system

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2412803A1 (en) * 1977-12-23 1979-07-20 Alkem Gmbh Continuous furnace for e.g. sintering nuclear fuel pellets - incorporates stop-start mechanism giving exact regulation of heating time
US4214868A (en) * 1978-06-21 1980-07-29 Itoh Iron & Steel Works Co. Ltd. Method of and an apparatus for soaking steel pieces
FR2487491A1 (en) * 1980-07-25 1982-01-29 Bmi Vacuum furnace for continuous heat treatment of metals - esp. for hardening saw blades made of high speed steel
US4396050A (en) * 1980-08-15 1983-08-02 Vandagriff Ralph L Log preparation for veneer peeling
US4527974A (en) * 1981-10-14 1985-07-09 Dario Carraroli Ceramic roller-hearth kiln with controlled combustion and cooling
US4518353A (en) * 1983-06-27 1985-05-21 Chugai Ro Co., Ltd. Vacuum sintering furnace
US4666402A (en) * 1985-05-30 1987-05-19 Flakt Ab Method and apparatus for preheating scrap in a bucket
EP0230740A3 (en) * 1985-12-11 1989-08-09 Australian Nuclear Science And Technology Organisation Container heating or sintering arrangements and methods
EP0234489A3 (en) * 1986-02-22 1989-08-30 Mahler Dienstleistungs-GmbH Löten-Härten-Anlagenbau Continuous furnace for heating and successively cooling work pieces
US4846717A (en) * 1988-03-30 1989-07-11 American Wheels De Mexico, S.A.D. E C.V. Continuous method and apparatus for the thermal treatment of metallic workpieces
US5613847A (en) * 1994-07-01 1997-03-25 Hans Lingl Anlagenbau Und Verfahrenstechnik Gmbh & Co. Heat transfer in a tunnel kiln
US6045357A (en) * 1997-09-22 2000-04-04 Japan Nuclear Cycle Development Institute Continuous sintering plant integrated with glove box for maintenance use
US20100044892A1 (en) * 2006-01-10 2010-02-25 Areva Inc Separating Device For Sintering Shoes
US20180212206A1 (en) * 2016-04-19 2018-07-26 Boe Technology Group Co., Ltd. Sintering apparatus, packaging system for organic light emitting diode device and sintering method
US11730045B2 (en) * 2016-04-19 2023-08-15 Boe Technology Group Co., Ltd. Sintering apparatus, packaging system for organic light emitting diode device and sintering method
WO2022068053A1 (en) * 2020-09-30 2022-04-07 苏州汇科机电设备有限公司 New atmosphere protection kiln

Similar Documents

Publication Publication Date Title
US4047886A (en) Furnace for the continuous sintering of pellets of ceramic nuclear fuel material
US2956381A (en) Packing apparatus and method
DE3378575D1 (en) A method and apparatus for loading a storage and transport rack
US20030226739A1 (en) Multi-level conveying apparatus and method
US4566835A (en) Nuclear fuel pellet sintering boat loading system
JP2024159351A (en) Exhaust device and atmospheric heat treatment furnace
US4470804A (en) Scrap material preheating apparatus
JPS6053723B2 (en) Continuous furnace for heat treatment of small parts
EP0533615A1 (en) Installation for the thermal treatment of successive charges
EP0171774A3 (en) Method for loading fuel rods in containers, apparatus for carrying out the method and container for storing fuel rods
DE2554422A1 (en) OVEN FOR CONTINUOUS SINTERING IN A CONTROLLED ATMOSPHERIC FOR AUTOMATED OPERATION
GB1276229A (en) A continuous furnace for sintering
CA1175163A (en) Storage of irradiated fuel assemblies
GB854764A (en) Improvements relating to nuclear reactor charging apparatus
US6431860B1 (en) Material feeding mechanism in association with continuous sintering apparatus
JPS54129656A (en) Cargo transferring method
US3884624A (en) Nuclear fuel preheating system
DE10206822B4 (en) Apparatus for coating bottles or other hollow bodies
JPS5648323A (en) Loading device
JPS54121400A (en) Radioactive waste storage facility
SU1187915A1 (en) Apparatus for sintering powder articles
JPS6176876A (en) Rotary type continuous hot hydrostatic pressing facility
JPS56127506A (en) Conveying method for goods
JPS58222280A (en) Storing installation
RU2038921C1 (en) Installation for sintering powder blanks